Motorad 606-221 Engine Coolant Thermostat Housing Assembly

Integrated Thermostat Housing for BMW Cooling Systems

Motorad 606-221 is an engine coolant thermostat housing assembly built for BMW and Rolls-Royce applications that use an integrated housing design. It combines the thermostat, housing, sensor, and seal in one OE-style service part for direct cooling system replacement.

With a 221 Deg. F opening temperature, bleeder hole, and jiggle pin, this Motorad Integrated Housing Thermostat is built to respond quickly to coolant temperature changes and help maintain stable engine operating temperature. The aluminum, stainless steel, and copper construction supports demanding cooling system service on BMW M models, X models, and select Rolls-Royce vehicles.

Key Features

• Part number: 606-221
• Integrated housing thermostat assembly for coolant system service
• 221 Deg. F start-to-open temperature
• Bleeder hole and jiggle pin included for air management
• Rubber seal included
• 3 bolt holes and 1 outlet port
• 1.51 in outlet diameter
• Silver finish
• OE supplier manufacturing with OEM specifications and processes
• Copper case and wax compound for fast temperature response

Product Details

Motorad’s Integrated Housing Thermostat line focuses on OE-style cooling system service parts built to match factory fit and function. This design uses OEM-style seals where applicable and an offset layout with an air relief valve to support proper coolant flow and easier air bleeding during service. The 606-221 is a direct replacement choice for BMW 760i xDrive, BMW M5, BMW X5, BMW X7, BMW X3, BMW M4, BMW M8, and other listed applications, as well as select Rolls-Royce Cullinan, Ghost, and Phantom models.

This part cross-references Dorman - OE Solutions 902-817 and Four Seasons 85956 for the same application.

Common Problems This Part Can Address

• Coolant temperature regulation issues caused by a worn thermostat
• Leaks at the thermostat housing or seal area
• Air trapped in the cooling system after service
• Slow thermostat response during warm-up or temperature swings
• Cooling system service needs on BMW and Rolls-Royce vehicles with integrated housings

Installation Notes and Tips

Verify the OE-style integrated housing layout, outlet diameter, bolt-hole count, and 221 Deg. F temperature rating before installation. Replace the seal during service, inspect mating surfaces for corrosion or residue, and bleed the cooling system carefully using the built-in bleeder hole and jiggle pin. Confirm vehicle-specific fitment for BMW M2, M3, M4, M5, M8, X3, X4, X5, X6, X7, XM, and select Rolls-Royce models before ordering.

Quality Assurance

Manufactured by an OE supplier using OEM quality materials, OEM specifications, and production processes. The copper case and wax compound are selected for rapid response to coolant temperature changes, and the assembly is built to meet the demands of modern automotive cooling systems.